EIP-712 Message Explainer

WHAT IT DOES

EIP-712 Message Explainer decodes and explains EIP-712 typed data messages before you sign them. The tool parses the typed data JSON, extracts the primary type, domain data (including the verifying contract address), and all message fields. It then detects the message type (Permit, Order, Transfer, Approval, Withdraw, Claim, or Custom), identifies dangerous patterns like unlimited approvals, and flags suspicious fields. The tool then uses AI to generate a plain-language explanation of what the message authorizes, what permissions it grants, and whether the request appears legitimate or suspicious. Results include a risk level, safety score (0-100), primary type, message type, verifying contract address, message fields with plain-language breakdown, flags, and a comprehensive AI-generated explanation. The tool operates entirely read-only — no transactions are sent, no signatures are required. The AI assessment is designed to help you understand what you are signing before you approve it.

HOW TO USE

Connect your EVM wallet using the "Connect" button in the header. Select the network where the verifying contract is deployed from the dropdown menu. Paste the EIP-712 typed data JSON into the text area — this is the structured data that your wallet will display when you are asked to sign. Click "Explain EIP-712 message" to begin the analysis. The tool parses the JSON, extracts the message structure and fields, detects the message type and patterns, and sends the data to the AI for a plain-English explanation. Results appear within seconds, showing the primary type, chain, risk level, safety score, message type, verifying contract address, message fields with plain-language breakdown, flags, and a comprehensive AI-generated explanation written in clear, conversational language.

EIP-712 MESSAGE PARSING AND PATTERN DETECTION

The tool uses a structured parsing approach to analyze EIP-712 typed data. It validates the JSON structure, extracts the primary type (the top-level message type), the domain object (which contains the verifying contract address and chain ID), and all message fields. The message type is detected by matching the primary type against known patterns — Permit (token approvals), Order (trading orders), Transfer (asset transfers), Approval (spender approvals), Withdraw/Claim (withdrawal requests), and Custom (unknown types). The tool also checks for dangerous patterns: unlimited approvals (the amount field set to max uint256 or containing "max"), unusual field names, high-value transfers, and unknown verifying contracts. The risk level is determined based on the message type and detected patterns: Permit with unlimited approval is High risk, Order and Transfer are Medium risk, and standard Permit with limited amount is Low risk. The safety score (0-100) is adjusted based on the risk level (80 for Low, 55 for Medium, 30 for High, 10 for Critical). The AI receives all this data and is prompted to explain the EIP-712 message in plain language — stating what the message is, what it authorizes, what permissions it grants, and whether the request appears legitimate or suspicious. The AI is also instructed to state plainly what it cannot verify — that it reads the EIP-712 typed data structure and fields, not the DApp's intent, off-chain consequences of signing, or the legitimacy of the verifying contract.

WHAT IT CANNOT SEE

This tool cannot definitively verify the intent of an EIP-712 message — only reads the typed data structure and fields. It cannot detect off-chain coordination or malicious intent not reflected in the typed data — a legitimate-looking message could be part of a coordinated attack. The tool cannot predict the outcome of signing — it can only explain the message structure and permissions. Legitimate EIP-712 messages may request broad permissions for valid reasons — a Permit for a large amount may be legitimate for a DeFi application. The tool cannot verify the identity or trustworthiness of the requesting DApp — it only reads the typed data. The tool cannot detect if the verifying contract is malicious. The tool cannot detect if the message has been tampered with. The tool cannot predict the future use of the signature. The tool cannot verify that the chain ID matches the current network.

PLEASE NOTE

EIP-712 Message Explainer supports EVM-compatible chains only (Ethereum, BSC, Polygon, Arbitrum, Optimism, Avalanche, and others). The tool is read-only and never requests wallet signatures or transaction approvals. Message explanations are AI-generated from the typed data structure — always review what you are actually signing in your wallet before approving it. The AI explanation is for informational purposes only and does not constitute financial or legal advice. Never sign an EIP-712 message you do not fully understand. Be especially cautious with Permit messages — they can approve unlimited token spending.